1. Field
Embodiments of the present invention relate to an organic light-emitting display apparatus, and more particularly, to an organic light-emitting display apparatus reducing color shift at side-view angles.
2. Description of Related Art
Organic light-emitting display devices are attracting attention as next generation display devices because the organic light-emitting display devices are not only driven at low voltage, are light and thin, and have a wide viewing angle and excellent contrast, but also, have they quick response speeds.
In an organic light-emitting display device, when a voltage is applied between an anode and a cathode, electrons and holes are combined in an organic light emission layer disposed between the anode and the cathode so that excitons are formed therein and emit light while the excitons drop from an excited state to a ground state.
An organic light-emitting display device generally emits light in a wide range of wavelengths, thereby reducing luminous efficiency and reducing color purity. Because light emitted from an organic light-emitting layer has no directivity, many photons from among photons emitted in a direction do not reach a viewer due to total internal reflection, thereby reducing extraction efficiency of an organic light-emitting device. Thus, a resonance structure may be formed in an organic light-emitting display apparatus by using a distributed Bragg reflector (DBR) mirror or by adjusting a thickness of an organic layer. However, although luminous efficiency may be improved, color shift may occur at side-view angles. That is, a viewing angle of the organic light-emitting display apparatus may be reduced.